I. Field of the Invention
The present invention relates to a cartridge adapted to be inserted in the body of a faucet, including a guide, an element of support for a movable small plate of hard material positioned within the guiding parts, at least one small plate of hard material which is fixedly mounted in the cartridge, and at least one movable small plate mounted in the element of support and adapted to move against the fixed small plate in order to effectuate the regulation of the rate of fluid flow and of the proportion of mixing.
II. Description of the Prior Art
In the usual construction, the element of support for the movable small plate and the parts which function as a guide are made of plastic material and their reciprocal sliding is facilitated by properly chosen plastic material and a lubricating grease. However, with time, the lubricating grease is expended, the plastic material loses its self-lubrication, and an excessive friction begins to develop between the parts which are subjected to a reciprocal sliding movement resulting in a clatter which is very unpleasant to the user. This inconvenience can be overcome in certain constructions by inserting thin gaskets of metallic foil between the parts of plastic material which are subjected to a reciprocal sliding movement. In fact, a proper choice of metallic material permits the avoidance of the development of excessive friction and of the noise which occurs with time when there is movement. However, the insertion of these gaskets has a relatively high cost, not only for their construction but because of the complications that they bring to the assembly of the cartridge. Further, this is not even possible in certain cases; for example, when one of the parts has a lamellar structure, an elevated structure or other structures which are destined to stop the vibration and the noise of the water flow.